1. Field of the Invention
The present invention relates to shaft position indicating systems, and more particularly to an opto-electronic shaft encoder conformed for inline mounting with a selected rotary shaft.
2. Description of the Prior Art
Shaft encoders utilizing photoelectric coupling have been known in the past. Most frequently as resolution and accuracy increases are desired, the radial size of these prior art encoders increases. This trade-off of accuracy against radial dimension has a compounding effect by increasing moment of inertia, which in the case of high speed devices may turn out to be prohibitive. Alternately, the radial clearance around a measured shaft is often insufficient to accommodate such prior art encoders, again precluding full utilization thereof. In addition, most of the prior art encoders are tightly packed with coating apertures, thus precluding convenient manual inscription of a specifically desired code. This tight packing further complicates sensor spacing both in dynamic systems use and in the convenience of assembly.